Means for locking circuit breaker operating handles



Feb. 5, 1963 H. 1. sTANBAcK ETAL 3,075,876

MEANS FCR LOCKING CIRCUIT BREAKER OPERATING HANDLES Filed Sept. '7. 1960 FE. I

HAP/QRS .2.' STAM/BACK CZE/VIENT PV. WOLF' "//MM ya@ United States Patented Fels. 5, i963 3,076,876 MEANS FOR LCEQNG CillCUllT @PEER-@ENG HANDLES Harris l. Stanbaclr, Lexington, Ky., and filament W. Woli, Mount Clement, Mich., assignors to Square D Con 1- pany, Detroit, Mich., a corporation of Michigan Filed Sent. 7, 19%, Ser. No. 51%,453 7 Claims. (till. Zitti-d4) This invention relates` generally to means for locking the operating handles `of circuit `breakers in selected position. More particularly, it relates to a padlock type handle locking device for use with panelboard mounted molded case type electric circuit breakers to lock the operating handle thereof in oft or on position.

It is an object of this invention to provide an improved handle locking device which is adapted to be removably attached to the case of a circuit breaker and to accommodate a padlock so that the hasp thereof interferes with movement of the circuit breaker operating handle from one position to another.

Another object is to provide a handle locking device of the aforesaid character which has improved means for attachment to the circuit breaker case, such means being concealed and rendered inaccessible by the trim pan or cover on the circuit breaker panelboard.

Another object is to provide a handle locking device of the aforesaid character which can be employed with circuit breakers of standard construction after a slight modification has been Amade in the cases of the latter.

Another object is to provide a locking device of the aforesaid character which is fabricated from a unitary piece of metal, which is economical to manufacture and which is easy to install in the factory or field With standard tools.

@ther objects and advantages of the invention will hereinafter appear.

The drawing illustrates a preferred embodiment of the invention, hereinafter described, but it is to be understood that the embodiment illustrated is susceptible of modification with respect to details thereof without departing `from the scope of the appended claims.

ln the drawing:

FIG. 1 is a side View of a circuit breaker 'having a handle locking device and a padlock associated therewith.

FIG. 2 is a View of one end of the circuit breaker and handle locking device shown in FIG. 1.

FIG. 3 is a view of the other end of the circuit breaker and handle locking device shown in FIG. l.

FIG. 4 is a top plan view of the circuit `breaker and handle locking device shown in FIG. l.

FIG. 5 is a top plan View of the handle locking device showing its configuration prior to association with the circuit breaker.

Referring to FIGS. 1 through 4, the numeral 1i) designatos a type of electric circuit breaker with which the invention is employed to great advantage. The circuit breaker li) may 'be assumed to be of standard construction and is a two-pole device having a pair of separable contacts (not shown) for each pole and an operating mechanism (not shown) foreach pole. Both operating mechanisms are simultaneously movable to open and closed conditions by means of an operating handle 11 which is pivota'lly movable between on and 01. posi tions, as FIG. 1 makes clear. Both operating mechanisms are automatically and simultaneously movable to open condition in response to an abnormal `circuit condition which aiects either one or both of the poles. The circuit breaker lil is of the trip-free type in that both mechanisms are -free to move automatically to open condition eveu though the operating handle il is held in on position. The circuit lbreaker 1t) is adapted for il es mounting in a panelboard (not shown) which, for ex ample, could be of the type shown in Patent No. 2,902,- 632 for Electrical Panelboard issued to Stanback et al. on September l, 1959 and assigned to the same assignee as the present invention. The panelboard is provided with a trim pan l2 having a knockout or hole i3 therein for accommodating the handle .il and portions of the case of the Icircuit breaker lid.

The circuit breaker iti comprises an insulating case lo which is fabricated `by stacking together a vbase portion 15, an intermediate portion lo, and a cover portion i7. 'l`ihe portions l5, 16 and 19.7', which are preferably molded from suitable insulating material such as Bakelite or the like, are secured together by means of a plurality of rivets iii. The portions 15, i6 and i7 are each provided with a molded projection and the projections combine to form a raised portion 1.9 on the circuit breaker case lll. As FlG. 4 best shows, the base portion i5 of the 'case lll is provided with a hole 2G through its molded projection for accommodating the operating handle 1l. The operating handle 1l, whch is molded from suitable insulating material such as Bakelite or the like, is understoodto be pivotally supported in a well-known manner between the base portion 15 and the intermediate portion le of the case lll. FIG. 1 shows the operating handle ll disposed in oil position and indicates the position it assumes when moved to on position.

ln accordance with the invention, the raised portion i9 of the case 14 is provided with locking slots 2l and 22 at opposite ends thereof. More specifically, the slots 2l and 22 are formed in the projection on the base portion l5 of the case i4 and are intersected by the plane in which the operating handle Ill moves. As FIGS. 1, 3 and 4 show, the slots 21 and 22 are disposed so as to lie below the level of the lower lsurface of the trim pan 12 when the circuit breaker `l@ is properly disposed in the panelboard.

Referring to FGS. l through 5, the numeral 2:3 designates a handle locking device which is constructed in accordance with the invention. The handle locking device 23 is a unitary member preferably fabricated by punching or stamping from heavy gauge sheet metal. The handle locking device 23 comprises a body portion 24 which is shaped to conform to the configuration of the raised portion l@ of the circuit breaker case lli. The body portion 24 of the handle locking device 23 is provided with a liange 25 which is integral therewith and extends upwardly or outwardly therefrom. The flange 25 is provided with a hole 26, best seen in FIG. l, which is disposed adjacent the operating handle il ot the cir cuit breaker l@ when the handle locking device 23 is associated with the circuit breaker. The hole 2d in the handle locking device 23 is adapted to accommodate the hasp 27 of a padlock 28 which may be of any well-known type. The body portion 2d of the locking device 23 is further provided with offset legs 29' and Sil at opposite ends thereof and the legs and 3Q are provided with locking tongues 3l and 52, resp ctively, which are adapted to engage the locking slots and 22, respectively, in the raised portion i9' ot the case ld of the circuit reaker it?, as will hereinafter be explained. The legs 7.9 and dit lie in a plane which is normal to the plane in which the iiange 25 of the locking device 23 lie-s. As lj'lGS. 4 and 5 show, the offset leg Zhi of the locking device 23 is provided with a notch or cutout portion 33 which weakens the leg sufciently in that area so that it may be bent from the position it occupies in FIG. 5 to that shown in ilG. 4, or vice-versa, as will be explained. The oiiset leg 2.9 or the locking device 23 is provided with a depression Pill which is adapted to accommodate the tip of a blade-type screw driver (not shown) which is employed to effect bending of the odset leg envases The invention is employed in the following manner.

T hand-e locking device 23 may be attached to the case llt of the circuit breaker either before or after the circuit breaker is attached to the panelboard, but in either event, before the trim pan l2 is associated with the circuit breaker. The handle locking device 23 is attached to the case ld or the circuit breaker lll by engaging the locking tongue 32 on the onset reg with the locking slot 22 in the raised portion l5 of the case rl`he handle locking device Z3 is then pressed down so that the body portion 2li thereof fits snugly against the raised portion i@ of the case ld. In this position the llange 25 of the locking device 23 lies in a plane which is parallel to but spaced apart from the plane in which the operating handle 1l of the circuit breaker ib moves. The locking tongue 33t of the leg Z9, which initially is disposed as shown in PEG. 5, is then aligned with the locking slot 2li in the raised portion 19 of the case llt. The tip of a blade type screw driver (not shown) is inserted in the depression 3d in the oilset leg Z9 of the handle locking device 23 and the screw driver is turned to twist the offset leg 29 in the clockwise direction (with respect to FlGS. 4 and 5) until the locking tongue 3l engages the locking slot 2l in the raised portion l of the case le. By this operation, the handle locking device Z3 is secured to the circuit breaker lll. rlhe circuit breaker Si@ is then installed in the panelboard, or if already installed, the trim pan l2 is put in place. Villen the trim pan l2 is in place, the raised portion lli? of the circuit breaker l0, the llange 25 and the body portion Zd of the handle locking device 23 extend thorugh the hole i3 in the trim pan. As Fl. 4 shows, the offset legs 2,9 and Si! of the handle locking device 23 are covered by the trim pan l2 and are not accessible from the front of the panelboard unless the trirn pan i2 is removed. The operating handle ll of the circuit breaker lo is now ready to be locked in either on or ott position.

To lock the operating handle ll in oil position, the handle is moved to the position shown in FlGS. l through 4, the hasp Z7 of the padlock 28 is inserted through the hole 2d in the tie-.nge 25 of the handle locking device Z3, and the padlock is locked in the usual manner. The hasp 27 of the padlock 2-3 is thus in position to interfere with pivotal movement of the operating handle il of the circuit breaker lll to the on position.

To lock the operating handle ll in on position the padlock 28 is removed in the usual manner, the operating handle is moved to the on position indicated in FG. l, and the padlock is attached to the handle locking device 23 as aforedescribed so that the hasp Z7 thereoi interferes with pivotal movement or" the operating handle to the od position.

it will be apparent that, it desired, the padlock 25s may be removed from the locking device 23 and the circuit breaker lil may be operated in the usual manner even though the handle locking device is still attached to the circuit breaker.

rthe handle locking device 23 may be detached from the circuit breaker 1lb without damage to either of them by removing the trim pan l2 of the panelboard, by ernploying a screw driver to twist the otlset leg in the counterclockwise direction (with respect to MGS. 4 and until the locking tongue 33; thereotF disengages the locking slot in the raised portion r9 of the case le, and by lifting the handle locking device to disengage the locking tongue 32 on the offset leg 3@ from the locking slot 22 in the raised portion or tre circuit breaker case.

Although the handle locking device disclosed herein is shown associated with a two-pole circuit breaker, it is apparent that it may be employed with circuit breakers having a greater or lesser number of poles provided they are suitably adapted as described herein.

What is claimed is:

l. In combination, a circuit controlling device having a case and a movable operating handle extending from said case, said case having slots therein near opposite ends thereof, a locking device naving a portion disposed adjacent the plane in which said operating handle moves, said portieri having au aperture for a padlock hasp therein, and a pair of detents integral with said portion at opposite ends thereof for engagement with respective slots in said case, one of said detents having a notch therein to facilitate bending thereof in opposite directions for re-V spectively engaging it with and disengagiug it from its respective slot, and a padlock having a hasp insertable in said aperture in said locking device whereby said hasp interferes with movemen of said operating handle of .said circuit controlling device from one position to another.

2. The combination according to claim 1 including a trim panel forming part of an enclosure for said circuit controlling devise, said trim panel having an aperture for accommodating the operating handle of said circuit controlling device and said portion of said locking device, said trm panel being adapted to overlie said detents to render them inaccessible for bending purposes.

3. In combination, a circuit controlling device having a case, said case having slots therein near opposite ends thereof, and an operating handle extending from said case and movable between two positions in a plane intersecting each of said slots, and a locking device having a portion lying in -a plane adjacent and parallel to said plane in which said operating handle moves, said portion having an aperture for a padlock hasp therein to lock said operating handle in either of its two positions and a pair ot detents integral with said portion at opposite ends thereof for engagement with respective slots in said case, one 4of said detents having a notch therein to facilitate bending thereof in opposite directions for respectively engaging it with and disengaging it from its respective slot.

4. A locking device for attachment to a circuit controlling device having an operating handle extending from the case thereof and movable in a plane between two positions, said case having slots therein near opposite endsthereof and intersected by said plane, said locking device comprising a portion adapted to lie in a plane adjacent and parallel to said plane in which said operating handle moves, said portion having an aperture for accommodating a padlock hasp, a pair of oitset legs integral with said portion at opposite ends thereof, each of said offset legs being provided with a dctent for engagement with a respective slot in said case, and one of said ofiset legs having a notch therein to facilitate bending thereof in opposite directions with respect to said portion of said locking device .for respectively engaging its detent with and disengaging its detent from the respective slot in said case.

5. The combination according to claim 4 wherein said one of said odset legs ot said locking device is provided with means for accommodating t-c tip of a screw driver to facilitate bending thereof.

6. A locking device for attachment to a circuit controlling device having an operating handle extending ,from the case thereof and movable in a plane betweentwo positions, vsaid case having slots therein near opposite ends thereof and intersected by said plane, said locking device comprising a body portion adapted to overlie the top o said circuit breaker, a flange portion integral with said body portion and adapted to lie in a plane adjacent and parallel to said plane in which said operating handle moves, said ilange portion having an aperture lfor accommodating a padlock hasp, and a pair of downwsrdly ollset legs integral with said body portion at opposite ends thereof, each of said offset legs being provided witn a detent for engagement with a respective slot in said case, each offset leg and its detcnt lying in a plane which is normal to the plane in which said oper ating handle moves, and one of said otset legs being provided With a notchy to weaken its attaclnnent to said body provided with a depression for of a screw driver to facilitate offset leg in the plane in which it portion and being furtner accommodating the tip bending of said one hes.

7. For a circuit controlling device having an operating handle extending outwardly from a front facing surface of a casing thereof and having a pair of recesses adjacent said front facing surface respectively in an opposed pair of side facing surfaces of said casing, a handle locking member comprising a body portion adapted to engage a portion of said front facing surface adjacent but spaced from said operating handle, a :flange portion integral with said body portion and projecting angularly from an edge portion thereof adjacent said operating handle,

said flange portion having a hole therein adapted to receive a padlock hasp in interfering relationship with operation of said operating handle, and a pair of inwardly extending detents integral with and adjacent opposite ends of said body portion and adapted to be received in said recesses to retain said handle locking member on said circuit controlling device.

References Cited in the tile of this patent UNITED STATES PATENTS 2,169,860 Von Hoorn Aug. 15, 1939 2,192,060 Wise Feb. 27, 1940 2,484,424 Rosing Oct. 11, 1949 

1. IN COMBINATION, A CIRCUIT CONTROLLING DEVICE HAVING A CASE AND A MOVABLE OPERATING HANDLE EXTENDING FROM SAID CASE, SAID CASE HAVING SLOTS THEREIN NEAR OPPOSITE ENDS THEREOF, A LOCKING DEVICE NAVING A PORTION DISPOSED ADJACENT THE PLANE IN WHICH SAID OPERATING HANDLE MOVES, SAID PORTION HAVING AN APERTURE FOR A PADLOCK HASP THEREIN, AND A PAIR OF DETENTS INTEGRAL WITH SAID PORTION AT OPPOSITE ENDS THEREOF FOR ENGAGEMENT WITH RESPECTIVE SLOTS IN SAID CASE, ONE OF SAID DETENTS HAVING A NOTCH THEREIN TO FACILITATE BENDING THEREOF IN OPPOSITE DIRECTIONS FOR RESPECTIVELY ENGAGING IT WITH AND DISENGAGING IT FROM ITS RESPECTIVE SLOT, AND A PADLOCK HAVING A HASP INSERTABLE IN SAID APERTURE IN SAID LOCKING DEVICE WHEREBY SAID HASP INTERFERES WITH MOVEMENT OF SAID OPERATING HANDLE OF SAID CIRCUIT CONTROLLING DEVICE FROM ONE POSITION TO ANOTHER. 